I've found on here that you need 4 square feet per bird in the coop. Right now we have 6 chickens in our enclosure which is 15' wide, 20' long, and 10' high. Inside the enclosure is a store bought coop/nesting box that is probably like 3' by 2' then it has a run, but I always leave the door to it open, as it's in the big pen. My chickens are happy and laying. And they come out into the pen around dawn and put themselves back in at night. I also let them run around my backyard when we are home, I just don't let them out there alone because I worry about hawks (and don't particularly trust my dog not to go after my silkie bantam when I'm not looking!). We just ordered 10 more chicks so I was going to built a second coop to put in the backyard enclosure. That way the new ones would have their own sleeping/laying place, but they'd all share the yard. When I saw 4ft per chicken in the coop I was shocked, I have no intention on making the coop 40 square feet! I was thinking like 5' by 5' which is more than double the one I have for my 6 now. Does this rule of 4sq feet apply when the chickens are out all day? We live in the south and don't really get snow so weather isn't really an issue. The enclosure not the coop comes out to be about 6 square foot per bird. Can I get away with a 5x5 coop to sleep 10 chickens? I was going to add another 3 or 4 nesting boxes on there too.